In the electrospinning process, a fiber-forming polymer is supplied to an electrically charged capillary flow tube in the form of a liquid at a relatively low viscosity. Volatile organic compounds are normally used to solvate the polymer to provide a relatively low viscosity solution or dispersion.
The use of volatile organic solvents which evaporate during electrospinning can lead to environmental problems. Moreover, the removal of residual amounts of organic solvents in the fibers increases the cost of the overall operation. Also, some polymeric solutions and dispersions have viscosities which are too high to enable economic production of fibers by electrospinning.